Private Branch Exchanges (PBXs) and voice mail systems are ubiquitous in offices around the world. Their capabilities for providing message indicators are, however, rigidly fixed and quite limited. For example, a typical PBX system may provide some indicator, such as a flashing message on an LCD panel on the user's phone, that a new voice mail has been left in the user's mailbox. However, the user must be present in the office to see this indicator. Similarly, voice mail systems may provide an indication of how many unheard voice mails are in the user's mailbox. However, the user must call the voice mail system to get this indication.
As workers become more mobile, and as the number and types of messaging and communication options expand (e.g. email, voice mail, faxes, pagers, cell phones, wireless personal data assistants (PDA's ) (e.g. RIM Blackberry, Palm Pilot, etc.), such conventional message indicators are becoming increasingly unsatisfactory.